So, Viscount Haldane has not been appointed the new Chairman of the Defence Select Committee of the Westminster Parliament. This is not a surprise, since he has been dead since 1928. But he would have done a fine job, I’m sure, had the speaker or any other member of parliament chosen to exhume him.

As I mentioned here, Haldane created the British Expeditionary Force, without which Britain and France would have been defeated in 1914; he created the Territorial Force, configuring it for war, which provided invaluable reinforcement to the Regular Army with troops that were at the very least semi-trained; and he galvanised the Liberal government to think about defence at least as much as they thought about social change. He is rightly regarded as a great reforming Secretary of State for War, before the post was merged with that of the First Lord of the Admiralty to create the new Ministry of Defence.

The new Chair – as it seems we must now call Chairmen – of the Defence Select Committee is Rory Stewart, Conservative MP for Penrith and The Border. That is up north, by the way, if anyone was confusing the border with the Welsh border; Conservatives can be elected beyond the southern constituencies.

He strikes me as a good candidate, not least because he has spent some time in the Army, albeit years ago and on a Short Service Limited Commission with the Black Watch. But there’s nothing wrong with these so-called ‘gap year commissions’. In fact, they are extremely valuable. They are designed not so much to bring people into the Army, but to give them a sniff of military life with a view to taking understanding and good will into the civilian world where it is hoped (expected) they will assume positions of responsibility and influence. It’s about civil-military connection rather than military capability.

He’s also done his walking tour of Afghanistan, worked for the Foreign Office and written a few good books. Not necessarily a guarantee he will do well in the job, but it’s a good start and his words on the limits and complexities of intervention are welcome in a political culture that seems a little too binary for my liking.

But we shall see. He certainly represents the new generation of politician, and I can’t help thinking many of them are a notch above their predecessors.

Perhaps this is a particularly interesting time to take the Chair. James Arbuthnot’s tenure was concerned with operations in Afghanistan, Iraq, Libya and the possibility of the same in Syria. Syria is still a live issue, but it seems this recent bout of interventions is over for a while.

What he will – and must – concern himself with is how the British Army – and the Royal Navy and Royal Air Force – reconfigure themselves after the latest round of cuts. Army 2020 is fast approaching. He must make sure the politicians have not made a horrendous mistake in cutting regular troop numbers, and he must make sure plans to rely more on the Reserves – formerly Haldane’s Territorial Force, later the Territorial Army – are workable.

The rule of law is what separates the civilised from the uncivilised – that and morality, of course. Not only does it define the things a society considers wrong, which are then called crimes, but it also deters people from committing those crimes – if, that is, they are accompanied by suitable punishments. Without this mechanism, society ends up being regulated not by reason, consideration and legitimacy, but by what is arbitrary and illegitimate. Violence and oppression ensue, followed by revenge and disorder – in other words, society becomes uncivilised.

I suppose we should, therefore, be happy that the rule of law has been allowed to take its course in relation to the conviction of a Royal Marine for murder while serving in Afghanistan. Murder is wrong, it is uncivilised, therefore people committing murder should be charged and, if found guilty through due process, punished. This, seemingly, is what has just happened at the Military Court at Bulford. Apparently it is the first conviction of its kind since the Second World War.

Senior officers have said the right things – and, no doubt, meant them. Brigadier Dunham, Deputy Commandant General Royal Marines, said: ‘It is a matter of profound regret that, in this isolated incident, one marine failed to apply his training and discharge his responsibilities.’ True, I’m sure. And: ‘It was a truly shocking and appalling aberration. It should not have happened and it should never happen again.’

It also goes without saying that whenever we fall short of our own exemplary standards, the critics and enemies of the very marines on trial seize on the opportunity for its propaganda uses. And there is, of course, the requirement to do the right thing (or not to do the wrong thing), no matter the circumstances. As General Sir Mike Jackson said: circumstances do not change the law.

Why, therefore, do I feel uneasy? It’s not just me. Major General Julian Thompson, Commander 3 Commando Brigade during the Falklands War, has reportedly refused to condemn the convicted sergeant, saying, ‘I’m not going to stand around bad-mouthing him.’ He has, of course, said that what happened was wrong, and that the law had been broken, but he clearly feels a certain conflict within.

After this verdict, which we are told carries a mandatory life sentence, there will be much discussion, especially in various barrack rooms across the Marines and the Army. Some will argue that he has been ‘hung out to dry,’ and they will do so in the fruity barrack-room language we might squeamishly prefer to think aberrant. Others, the other side of the fence, will say that this case should be followed by many more just like it. Individual prejudices, which we all possess, will determine which view people are most likely to take.

But the thing that sits uneasily is the simple fact that none of this would have happened if the marine in question had not been sent to Afghanistan to fight a war on behalf of his government and his country. He chose to serve, of course, but he was only in that specific situation because his country put him there. And neither am I aware of any evidence – though I may have missed it – to suggest he is the sort of person who breezily shoots people on the way to the shops at home. No. The circumstances were unique. He was in Helmand.

This is not an argument, of course, that excuses law-breaking. People commit crimes while at ‘work’ all the time. It’s no excuse. But, being sent to fight a war – and this deployment subjected these servicemen to experiences of a particularly vile nature – puts the person in question under unique stresses and strains. It is like no other. No other job involves going to a place of work where your competitor is not just trying to do better at this particular ‘business,’ but actively trying to kill you. Indeed, we are told that twenty-three of his colleagues were killed on the same tour. This changes the work dynamic, doesn’t it? How do we know how we would react in a similar situation?

Marine A is, incidentally, called Marine A because the authorities fear reprisals. We might say this could apply to the families of all those convicted of murder. But it doesn’t. This is a different situation. The problem in this case is the way the ‘friends’ of the victim operate. They are unremittingly uncivilised. We saw their modus operandi in Woolwich. They have no rule of law; they only have arbitrary, medieval barbarity – and that’s doing the word medieval a disservice. That’s what Marine A was fighting against. Again, how do we know the effect of this type of environment on otherwise law-abiding people?

But we have the rule of law, as I said earlier. This is what makes us different. The court will have heard the charge and the evidence and made what it thought was the right decision. I suppose, despite any reservation we might have – especially from ex-soldiers and ex-marines – this is the sort of thing our Armed Forces are there to fight for. And if we do not live by our own rules, how can we expect others to recognise the superiority of our system?

It’s just rather saddening, as General Sir Mike Jackson said, that’s all. Casualties of war are more numerous than we might think. It’s not just the killed and the wounded. Almost everyone who has served is affected in some way by that service. And this, it seems to me, is just one more example. Marine A did the wrong thing. He has paid for his mistake. But if some of us are going to condemn him, we should probably thank him too – for being prepared to serve and risk his life for his country in the first place. His life, like so many other lives, is never going to be the same again, all because he volunteered to serve.